Debarker with beater rotors under the log



March 10, 1959 c. D. WALDRON DEBARKER WITH BEATER ROTORS UNDER THE 1.0a 195s 2 Sheets-Sheet 2 Filed March 3 l/VVENTOR United States Patent 2,876,812 DEBARKER WITH BEATER ROTORS UNDER THE LOG Cloyd D. Waldron, Glenwood, Ark. Application March 3, 1955, Serial No. 491,928 4 Claims. (Cl. 144-208) This invention relates to machines that quickly and automatically remove the bark from wooden posts and poles without reducing the dimensions of the wooden part of the post.

More specifically the invention is directed to wooddebarking machines in which chains that are attached to one or more rotors strike the bark on a piece of round wood while it is rotating and moving past the rotating rotors. In a size of machine that is suitable for fence posts the post is supported, rotated, and moved by powered feed rollers against which the post is pressed by the striking action of the chains. In a size of machine that is suitable for logs, the weight of the log will press it against the chains and against the feed rollers.

According to the preferred form of the invention for debarking posts the chains are divided into groups along the rotors with feed rollers located outside and between the groups so as to more positively assure post movement, and to prevent posk kick-up when a post is entering or leaving the machine.

The chains must be of sufiiciently large size and sufiicient in number so that when the chains strike bark on posts the bark will be removed from the wood. The rotors must turn at a suitable low speed so that when the chains strike Wood from which removed the wood will not be damaged.

Prior to the present improvements a large number of posts were debarked by hand. Hand methods were slow, expensive, and usually left much bark on the posts. Some posts and most pulpwood were debarked in tumbling barrels. Tumbling barrels were large, expensive and slow. Tumbling barrels required hand removal of fragments of bark after tumbling. Some posts and most poles were debarked by machines in which the pole ro- 5, 6, and 7 of one debarking rotor.

' rotor 8, 9, 16,

the bark has been 1 i tated and passed underneath a movable rotor that had knives on its outer surface. These knife machines removed wood in addition to bark, reducing the size or grade of the pole. log axially through a machine in which a rotating head pressed scrapers against the log, scraping off the bark. These machines wereexpensive, slow, and limited in the size of log a single machine could accommodate. Logs also were debarked by rotating them on adjustable rollers and moving a rotor that had chains on its outer surface along the length of the log, off the log. This required a complicated machine for setting and controlling the rollers and for moving and controlling the chain rotor.

An object of the present improvements is to provide Logs were debarked by passing the two rotors.

the chains knocking the bark 1 a wood debarker in which the large forces exerted by part These and other objects will be manifest from a conposts so that the forces from posts downward against the posts above a level plane sideration of the following description, claims, and drawings in which:

Fig. 1 is a top view of a preferred form of the invention' with two parallel debarking rotors, and with several feed rollers along the length of the rotors.

Fig. 2 is an end view of the machine in Fig. 1, showing the relative locations of the debarking rotors, feed rollers, piece of wood being debarked, and the driving means.

Fig. 3 is a side view of a debarker with one rotor.

Fig. 4 is a section 4-4 taken from Figure 3.

Referring to Fig. 1, there is illustrated a frame 1 to which are attached bearings 2 and 3. The bearings 2 and 3 are supported by columns 51 and 52, which are part of the rigid frame of the machine. In the bearings 2 turns a shaft 4, to which shaft are rigidly attached parts In the bearings 3 turns a shaft 8, to which shaft are rigidly attached parts 9, 10, and 11 of a second debarking rotor. To the outer part of rotor 4, 5, 6, 7 are attached one end of each of the lengths of chains 12. To the outer part of 11 are attached one end of each of the lengths of chain 13. The unattached ends of the chains 12 come near, but do not strike the unattached ends of the chains 13 during rotation. The rotor 4, 5, 6, 7 is substantially parallel to the rotor 8, 9, 10, 11.

In the region between the two rotors where the chains 12 are near the chains 13, powered feed rollers 14, 15, 16, and 17 support a piece of wood 18 that is being debarked. The rotational axes of rollers 14, 15, 16, and 17 are skewed with respect to the cylindrical axis of the workpiece or post 18 so that as such, workpiece rolls on the rollers it also moves axially. This feeds the post 18 through the machine and exposes all parts of its cylindrical surface to pounding action from the chains 12 and 13. A trough 19 supports the post 18 as it is entering the machine. The trough 19 is supported by columns 53 and 54, which are part of the rigid frame 1 of the machine. A trough 20 supports the post 18 as it is leaving the machine. Likewise the trough 20 is supported by two columns that are part of the rigid frame 1 of the machine, the columns that support the trough 20 corresponding to the columns 53 and 54 that support the trough 19.

Fig. 2 shows the relative elevations of the rotor 4, 5, 6, 7, the rotor 8, 9, 10, 11, the feed rollers 14, 15, 16, and 17, and the post 18. Pulleys 21 and belts 22 turn the The rotor 4, 5, 6, 7 turns clockwise, whereas the rotor 8, 9, 10, 11 turns counterclockwise. Pulleys 23 and belts 24.turn the feed rollers 14, 15, 16 and 17. The feed rollers 14, 15, 16, and 17 are mounted for free turningon shafts 55, which are supported by vertical columns 56. The columns 56 are part of the rigid frame 1 of the machine. The belts 22 and 23 are driven by pulleys on a shaft 25. The shaft 25 is powered by a motor or any suitable power-generating device that turns the shaft 25 at substantially constant speed. Shoes 26 are pivotally supported by columns 57 that are part of the rigid frame 1 of the machine. Springs 58 pull the shoes 26 against the post 18, pressing it against the feed rollers.

The operation of the embodiment illustrated in Figs. 1 and 2 is as follows. With the machine running, a post 18 that has bark is placed on the trough 19 and rotating feed roller 14. When the forward part of post 18 is pushed into the space between the rotor parts 5 and 9 the chains 12 and 13 on the rotor parts 5 and 9 strike the post 18, removingsome bark and pressing the post downward against the feed roller 14. Pressure between the feed roller 14 and the post 18 causes the post to rotate and move forward onto the rotating feed roller 15,

After the post 18 has moved onto the roller 15 this roller helps prevent kick-up of the trailing end of the post during the time that the forward end of the post proceeds between the rotor parts 6 and 10, when more chains strike downward onto the front end of the post 18, removing more bark. By the time the post has gotten between the rotor parts 7 and 11 most of the bark has been removed and the chains on these parts 7 and 11 do a finish-cleaning action. The trough 20 helps keep the post in proper position for debarking until the trailing end of the post has passed over the roller 17.

The feed rollers 14, 15, 16 and 17 can be firm inaterial with irregular outer surfaces that will grip and move the post 18. Pneumatic tires on these rollers will firmly grip and move the post 18, and will absorb the "ibration that is caused by the debarking chains striking the post 18. Pneumatic tires will deflect and allow posts that have irregularities on their surfaces to continue rotating and moving smoothly over the rollers.

Referring to Fig. 3 and Fig. 4 there is shown a log 'd'ebarker having only one chain rotor 39, and two feed rollers 40 and 41. 7

From the above description it is believed clear that there is herein provided structures in which approximately round lengths of wood are passed near and parallel to rotors that have lengths of chain attached to them. The lengths of chain extend outside the rotors during rotation and strike the lengths of wood. Feed rollers whose axes are skewed with respect to the longitudinal axis of the wood cause the wood to rotate and feed through the machine, exposing all cylindrical surfaces of the wood to the striking action of the chains, removing all bark from the wood. Flexible members like chains reach into depressions and -around bumps so as to remove all bark from wood that has irregularities on its's'urface.

The use of two rotors with chains permits balancing the large force on the piece of wood that 'is generated by large numbers of chains striking the wood, and permits a shorter machine while still using a large number of chains. Large numbers of chains on low-speed rotors will remove bark from wood without damaging the wood when they strike debarked wood. The process of having the chains strike the already debarked part of the wood across the grain instead of parallel to the grain permits slightly higher debarking speed without wood damage.

The use of low-speed rotors with many attached chains for debarking pieces of wood that move near the rotors in a direction parallel to the rotor axes provides a machine that has many advantages. It rapidly, "aut or'natidaily, and completely removes the bark "from woodposts, poles, pulpwood, and logs without removing any wood. By not removing any wood fromposts and poles "higher grades are m'aintained. By not, removing any'wood'from vpulpwood and logs all the valuable-part of "them is s avcd.

The elimination or hand cleaning of posts and poles after going through a debarkin-g machine is an important improvement.

Applicant does not Wish to be limited to the above description or 'to the illustrated embodiments but instead only by the scope'ot the appended claims and their equivalents.

What is claimed is: 7

1. A machine that removes bark from wood, said machine being composed of two rotors and some feeder rollers, with means for driving 'said rotors and rollers, said rotors having substantially parallel axes of'rotation, said rotors having lengths of chain attached to'them in a manner that permits centrifugal'force during rotation to cause parts 'of said lengths of chain to extend outside said rotors in directions away from their axes of rotation, said two rotors being spaced so that said extended lengths of chain on one rotor comenear but do notstrikerthe t n ed. l n th fas e s 9n he, e rm q s ds a ing being such that th e chains strike a piece of wood that the region where the extended lengths of chain on the two rotors come near each other, said rotors having rotational directions that press such piece of wood against said feeder rollers, said two rotors having matching spaces along their lengths in which no chains exist in the entire circumference of each of the rotors, said feeder rollers rotating about axes that are not parallel to said rotor axes but that are substantially parallel to a plane that contains both axes of said rotors, said rollers being located in positions that support such piece of wood in the region in which the extended lengths of chain on the two rotors come near each other, the longitudinal axis of such piece of wood being substantially parallel to the rotor axes of rotation, said rollers having peripheral surfaces that cause such piece of wood to rotate and move axially, some of said rollers being located axially beyond both ends of the parts of said rotors to which the chains are attached, and other of said rollers being located at said matching spaces along said rotors in which no chains exist.

2. In a machine that removes bark from wood, poweroper'ated means for whirling chains around an axis of rotation, and additional power-operated means for moving a piece of wood axially and rotatively past said chains in amanner that causes the chains to strike such piece of wood on difierent areas as such piece of wood moves, said of rotation of said means for whirling being located at an elevation lower than a bottom surface of such piece of wood and extending substantially parallel to the axial direction of movement of such piece of wood.

3. In a machine that removes bark from wood, two power-operated rotors that have substantially parallel axes of rotation, members mounted on said rotors, said members having flexibility, and additional power-operated means for moving a piece of wood axially and rotatively past said members in a manner that causes the members to strike such piece of wood on dilierent areas such piece of wood moves, the two rotors turning in opposite directions that cause the members to press such piece of wood against said means for moving, the axes of the rotors being located at an elevation lower than a bottom surface of such piece of wood and extending substantially parallel to the axial direction of movement of such piece of Wood.

4. In a machine that removes bark from wood, poweroperated means for whirling members around an axis of rotation, said members having flexibility, and additional powered rollers'for supporting and moving a piece of wood axially and rotatively past said members in a manher that causes the members to strike such piece of wood on different areas as such piece of wood moves, said axis of rotation of said means for whirling being located at hnelevation lower than a bottom surface of such piece of whorl andextending-substantially parallel to the axial is put into direction-oi? movement of such piece of wood.

"References Cited .in the file of this patent UNITED STATES PATENTS f f915,91 9 Wilkinson Ma1'f23, 1909 987,828 "Schenck Mar.'28, 1911 "1,473,582 Lee dom Nov. 6, 1923 1,889,046 Foss Nov. 29, 1932 2,012,716 Colche'nsky Aug. 27, 1935 2,341,640 Mehlhor n Feb. 15, 1944 2,461,924 Robertson Feb. 15, 1949 2,505,168 Augustin Apr. 25, 1950 2,520,421 Mathewson et al Aug. 29, 1950 "2,601,261 Carpenter June 24, 1952 2,652,867 Boswell Sept.22, 1953 1' -"2,655;'9 6l McComb Oct. 20, 1953 2,713,365 Raut'nig July 19, 1955 J H FORiEIGN PATENTS 6,343 Great Britain -.'..;.-.--Mar. 26, 1901 44,4 .2 3 ,s dmshamans, Mar. ;9,;1 954 367,535 France Sept. 6. 1906 

